This invention relates to a laundry machine that can wash and dehydrate laundry. During dehydrating, the machine removes water from the laundry, but leaves the laundry damp.
The following three types of such laundry machine are known.
The first type of the laundry machine comprises a water container, a perforated dehydrating tub supported in the water container for rotating about a vertical axis, and an agitator rotatably supported in the dehydrating tub. To wash and rinse the laundry, the laundry is loaded in the water container, water is supplied to the water container, and the agitator is rotated. Subsequently, water is drained from the water container, and the dehydrating tub is rotated at high speed to dehydrate the laundry.
The laundry machine of the second type comprises a water container and a perforated rotation drum. The rotation drum is supported in the water container so that the drum can rotate about a horizontal axis. After the laundry is loaded in the rotation drum and water is supplied to the water container, the rotation drum is rotated to wash and rinse the laundry. Subsequently, water is drained and the rotation drum rotates at high speed to dehydrate the laundry.
U.S. Pat. No. 2,171,499 proposes the third type of the laundry machine which comprises a water tub, a ring supported in the water container for rotating about a vertical axis, a perforated spherical container supported in the ring for rotating about a horizontal axis, a drive means for rotating the spherical container and the ring, and a change means for controlling the drive means and for choosing one between the horizontal and the vertical rotations of the spherical container and the ring. After the laundry is loaded in the spherical container and water is supplied to the water tub, only the container rotates about the horizontal axis to wash the laundry. Subsequently, in order to dehydrate the laundry the water is drained and the ring and the container rotate about the vertical axis at high speed.
In the first washing machine, however, large amount of water is required for washing the laundry because the laundry is washed and rinsed by the water driven by the agitator. In addition, the laundry is entangled and the dehydrating tub loses its balance after washing operation. Therefore, the dehydrating tub is apt to abnormally rotate at the beginning of the dehydrating operation.
The second type of the laundry machine requires less water and has less entangled laundry than the first laundry machine. However, after the laundry is washed, the laundry accumulates in the bottom of the rotation drum. In the next dehydrating process, the rotation drum rotates about the horizontal axis at high speed, resulting in the following problem. Specifically, during the rotation the rotation drum loses its balance and vibrates due to the unbalanced load of the laundry, thus generating noise. Weights for preventing the noise makes the laundry machine heavier and manufacture cost becomes high.
The third type of the laundry machine has the following problem when the ring and the spherical container rotate about the vertical axis at high speed especially in the dehydrating operation. Specifically, the container, which is not fixed to or regulated by the ring, is allowed to rotate about the horizontal axis when rotating around the vertical axis at high speed. When the container with the laundry accumulated at its bottom rotates with the ring about the vertical axis at high speed for dehydrating the laundry after the washing operation, the laundry is pushed up to the horizontal axis due to the centrifugal force. Especially when the center of gravity of the laundry is beside the bottommost of the spherical container, the centrifugal force is generated in the direction of the center of gravity, thus inclining the container about 90.degree. in the direction, when the container rotates with the ring in such condition about the vertical axis at high speed, it loses its balance, vibrates and generates noise. Consequently the laundry cannot be properly dehydrated in such a case.